The present disclosures relate to integrated circuits, and more particularly, to an integrated circuit with memory and a method of configuring a memory.
Generally, it is impossible for a processor to run from its conventional Flash memory if that same memory is busy. The memory may be busy in view of erasing, re-programming, check summing, etc. Opcode fetches from a busy flash are not allowed and typically return garbage or an Access Error interrupt. Any microcontroller application requiring mission mode reprogramming of Flash memory must therefore employ a microcontroller which includes a second physical block of program memory or a mechanism to stall the core while the Flash is busy. Requiring a second physical block of program memory is costly.
With advancements in integrated circuit technology, it would be desirable to obtain a reduction of die size and cost. However, a common approach to meeting a mission mode Flash reprogramming requirement is to provide a distinct Boot Flash or Program RAM block on the integrated circuit die. Such memory blocks consume significant die area, especially so when considering the very infrequent uses of such resources during the mission.
Accordingly, there is a need for an improved method and apparatus for overcoming the problems in the art as discussed above.
The use of the same reference symbols in different drawings indicates similar or identical items. Skilled artisans will also appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help improve the understanding of the embodiments of the present invention.